What Is the Reason behind Earth’s Magnetic Field?

Earth’s magnetic field has been a debate since the 13th century when the philosophers noticed lodestones turning north for the first time. Queen Elizabeth’s physician, William Gilbert brought it in the spotlight stating that the globe is a great magnet. Scientists now think that Earth is an electromagnet. They believe the Earth is a source of a magnetic field which is a large electric current of billions of amperes. It is said to be in the core fluid of the Earth.

This believed magnetic field in the core of the Earth has been questioning the scientist minds since forever. Nobody has ever developed an urge to go for the mythical journey and figure out the real science. No one has ever taken the journey to the center of the Earth and has been able to evaluate the physics behind this.

Shockwave Study

By studying the shockwaves of earthquakes that travel throughout the planet, scientists have been able to lightly describe its structure. In the center of the Earth, there is a hard inner core that is supposed to be two-thirds of the Moon’s size. This core is completely composed up of iron. At 57,000 C hellish, this core iron becomes as hot as the surface of the Sun. When it reaches such a point, the pressure of crushing caused by gravity helps to prevent it from turning into liquid.

Inner Core Behavior

The center core has got a thick layer of 2,000 km of nickel, iron and other quantities of metals. The metal in the inner core is present in the fluid form. The difference in temperature, composition, and pressure of the outer core ignites convection currents and the molten metal becomes cool, the dense matter becomes warm and furthermore, the less dense matter comes above. Coriolis force due to which the Earth is able to spin is also responsible for swirling whirlpools.

The flow of the liquid iron is responsible for generating electric currents that in return produce magnetic fields. The charged metals that pass through these fields make the electric current on their own and continue the cycle. This self-sustaining loop cycle is known as geodynamo.

Overall, the spiraling occurring through the Coriolis force means that there are separate fields created which roughly align in one direction. The combined effect of these fields keeps on adding up and makes up an entirely large magnetic field that engulfs the planet.

The past studies reveal this concept about the Earth’s magnetic field. The history plays an important role in bringing the topic to the table. Even after the variations, the magnetic field has been losing its energy and cannot possibly be more than 10,000 years old. Now, the Earth’s magnetic field is no longer a history.